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How Do I Read My Propane Gas Gauge?

How do I read my propane gas gauge?

If your home is powered by propane, you’ll have to keep an eye on how much gas is in the tank so you know when you need to schedule a propane delivery. The question is, how do you read that gauge?

In some small gas cylinders (such as the 20-lb. tank for your barbecue), there is no gauge – the best way to judge how much gas is left is to simply weight it. Most propane grill tanks come with two numbers stamped on the handle – the water capacity (“WC”) and “Tare Weight” (TW – the weight of the tank when it’s empty). Most grilling tanks weigh about 17 pounds when empty and hold about 20 pounds of gas; to measure how many pounds of propane are left in your tank, simply weigh it on a scale and subtract the TW number. For example, if a tank weighing 27 pounds has a TW of 17 pounds, there’s about 10 pounds of gas left – a little more than half a tank.

Things get easier with larger, whole-house tanks (100+ gallons), which usually have a fuel gauge (often located under the tank dome or cover). The gauge usually looks a lot like the gas gauge in your car, with numbers that show the percentage of the tank that is full. Most gauges read from 0 to about 90 percent (see why 90 percent and not 100 percent below); a gauge reading of 10 means that the tank is 10 percent full (almost empty).

We recommend that you schedule a propane delivery when your tank is no less than 25 percent full – especially during heating season – to avoid a propane run-out.

Why isn’t my propane tank 100 percent full?

If you’re a keen observer, you might have noticed that your propane tank is never 100 percent full. Why? It’s a question of propane safety.

Much like water, propane expands when it’s heated. But propane expands to about 17 times the volume of water over the same temperature increase! The extra space in the tank allows for that expansion.

Above-ground propane tanks are typically filled to about 80 percent capacity; underground propane tanks can be filled slightly higher, because the ground insulates the tank from big temperature swings.

Our expert drivers use a fixed liquid level gauge to make sure we don’t overfill – a simple but important measure we take to make sure every delivery to your home is a safe one.

For safe propane deliveries in western Massachusetts, trust the pros at FSi. Contact us to schedule a propane delivery today!